M30240ECFP MITSUBISHI [Mitsubishi Electric Semiconductor], M30240ECFP Datasheet - Page 140

• Manufacturer Part Number: M30240ECFP
• Description: M30240 Group Specification
• Manufacturer: MITSUBISHI [Mitsubishi Electric Semiconductor]

Specifications in this manual are tentative and subject to change
USB Transceiver
5.4 USB Transceiver
Figure 1.122: Configuration of External USB components
When using the on-chip voltage converter to supply the necessary 3.3V to the driver circuit, a capac-
itor network must be connected between Ext. Cap (pin 6) and V
quired as shown in Figure 1.122. The high frequency 0.1 F capacitor should be an X7R type or better.
The low frequency decoupling capacitor of 2.2 F should be of tantalum di-electric or better. The start-
up time for this value of the capacitor is 3.2 ms, approximately (1ms/ F) + 1 ms.
After enabling the on-chip voltage converter, a certain amount of time must pass before a wait or stop
clock instruction is executed. The amount of time is given by (C+1) ms, when C is the value in F of
the external capacitance connected to the Ext. Cap pin. For example, if the external capacitance is
2.2 F, at least 3.2 ms must elapse from the time that the on-chip voltage converter is enabled until a
WAIT instruction or STOP command (CM10 = 1) is executed.
In order to meet the impedance matching requirements of the USB Specification, a 33
be added to USB D+ (pin 9) and to USB D- (pin 10). In addition, capacitors connected between USB
D+ and USB D- or USB D+/D- and Vss may need to be added for rise/fall time matching and edge
control. These capacitors should be placed after the 33
will depend on the PCs layout. The placement of external components is illustrated in Figure 1.122.
Note: Capacitor values and configuration may depend on PCB layout.
USB Block
USB_Suspend
USB_Vm_out
USB_Txen_n
USB_Vp_out
USB_Vm_in
USB_Vp_in
‘
USB_Rxd
1-140
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
XCV_Vp_out
XCV_Suspend
XCV_Txen_n
XCV_Vm_out
XCV_Rxd
XCV_Vp_in
XCV_Vm_in
Voltage Converter
Transceiver
resistors. Their configuration and values
+
_
SS
(pin 13). Two capacitors are re-
Mitsubishi microcomputers
M30240 Group
Ext Cap
2.2 F
D+
D-
10%
33
33
=
33 pF
22 pF
resistor must
0.1 F 10%
(Note)
=
22 pF